The long-awaited Westfield World Trade Center mall in the gargantuan World Trade Center Transportation Hub “Oculus” opens on Tuesday after years of delays and cost overruns. Nearly 100 fancy stores, including Apple, Turnbull & Asser, Tumi and Sephora, line both sides of the gridiron-length, ovoid space on two levels — like a supermall at a Middle East airport.

The stores follow the new Eataly, which opened last week on the third floor of 4 World Trade Center, which connects with the Oculus. The gourmet Italian food market where Mario Batali’s a partner isn’t as big as the uptown original, but it has great views of the skyline.

Overnight, the former shopping desert around the World Trade Center has blossomed into a luxury-goods paradise. And its pieces all fit together so you never have to go outside.

The Oculus is the middle link in a shoppers’ and noshers’ promenade that stretches from the MTA’s doughnut-topped Fulton Transit Center on Broadway all the way to Brookfield Place near the Hudson River.

Even with a few fast-food joints, the Fulton Center atrium had an empty feel until Shake Shack opened there a few weeks ago. Now it’s a buzzing beehive with the aroma of griddled beef in the air.The Mac store is ready to open Tuesday at Westfield World Trade Center Oculus.Lois Weiss

A passageway connects the subway complex to the Oculus’ eastern end. The Oculus floor leads to the PATH station, where a marble-clad tunnel runs astride the base of 1 World Trade Center to escalators which in turn lead to Brookfield Place.

Brookfield, anchored by the palm-tree-filled Winter Garden, boasts its own luxury boutique lineup including Bottega Veneta, Gucci, Hickey Freeman and Davidoff — as well as sprawling Le District (the “French Eataly”) and the Hudson Eats food court.

But are a bunch of new stores worth the nearly $6 billion in mostly public money it took to create them?

The Oculus and the Fulton Center have been called a waste since the projects started more than 10 years ago.

The Post, most other media and elected officials have blasted them as “boondoggles” to feed agencies’ and architects’ egos, when the money could have been better spent on adding subway tracks and helping pay to replace buildings destroyed on 9/11.

But the new stores and eateries are pumping life and energy into a site that 15 years ago seemed dead forever.